The wet hot air enters the dryer through 3 way valve [v-1], where it change the direction diret towards 4 way ball valve v-2 in heating cycle and towards 4 way ball valve thru pre cooler in cooling cycle.
Heating
The regeneration of desiccant is carried out by hot air. This air passes through port [1-2] of 3 way valve [v-1] enters the 4-way valve [v-2] wherefrom it is directioned to the adsorber tower [ads-1], which is in regeneration mode, through the port [3-4]. The hot air heats the desiccant bed and expels the moisture present in desiccant. The air after passing through the ports [4-1] of 4-way valve [v-3] enters into the regeneration cooler [rc-1]. The air gets cooled to inlet air temperature in the cooler and enters the moisture separator for moisture separation. After moisture separation, it enters into adsorber tower [ads-2] via ports [1-2] of 4 way valve [v-1] for adsorption [drying].
Cooling
When the desiccant gets heated up by hot air it is to be cooled upto drying inlet air temperature for effective drying.
For cooling, air passes through port [1-3] of 3 way valve [v-1] get cooled upto 40°c and moisture separated, while passing through pre cooler and moisture separator and enters the 4-way valve [v-2] wherefrom it is directioned to the adsorber tower [ads-1], which is in regeneration mode, through the port [3-4]. The air cools the desiccant bed and expels the moisture and heat present in desiccant. The air after passing through the ports [4-1] of 4-way valve [v-3] enters into the regeneration cooler [rc-1]. The air gets cooled to inlet air temperature in the cooler and enters the moisture separator for moisture separation. After moisture separation, it enters into adsorber tower [ads-2] via ports [1-2] of 4-way valve [v-1] for adsorption tower [ads-2] via ports [1-2] of 4 way valve [v-1] for adsorption [drying].
Adsorption
The full air flow passes through the 4-way valve [v-2] through the port [1-2] and enters the adsorber tower [ads-2] wherein it is dried while passing through the desiccant bed. This dried air enters the after filter [af-1] after passing through the port [2-3] of 4-way valve [v-3]. The after filter removes the desiccant dust and after cooler maintain desired outlet air temperature and supplies dry, filtered air at the outlet of dryer.
This way when one desiccant bed dried the air. Other bed gets reactivated and vice-versa this change over is achieved by the help of plc.
